۞ And remember the brother of Ad, when he warned his people beside the sand-dunes -- and already warners had passed away alike before him and behind him -- saying, 'Serve none but God! Truly I fear for you the chastisement of a dreadful day. 21 They said, “Have you come to us in order to turn us away from our Gods? Therefore bring upon us what you promise us, if you are truthful.” 22 He said, “Its knowledge is only with Allah; and I convey to you the messages of my Lord, but I perceive that you are an ignorant nation.” 23 Then, when they beheld it as a dense cloud coming toward their valleys, they said: Here is a cloud bringing us rain. Nay, but it is that which ye did seek to hasten, a wind wherein is painful torment, 24 Destroying everything by the command of its Lord, so they became such that naught could be seen except their dwellings. Thus do We reward the guilty people. 25 And We had established them in that wherein We have not established you, and We appointed for them hearing, and sight, and hearts; and yet their hearing, their sight and their hearts availed them nothing, since they denied the signs of God, and they were encompassed by that they mocked at. 26